In some embodiments of prior art ferrules used in broadheads, the diameter of the ferrule body is substantially the same as the diameter of the shaft of an arrow or crossbow bolt to which the broadhead is attached. As such, the distal end of the shaft and the proximal end of the ferrule body abut and are substantially aligned when the broadhead and the shaft are attached to each other. In certain embodiments of prior art ferrules used in broadheads, the diameter of the ferrule body is relatively smaller than the diameter of the shaft of an arrow or crossbow bolt to which the broadhead is attached. As illustrated in FIG. 1, the base or the shoulder of the ferrule body, i.e., the portion of the ferrule body that abuts the shaft, is typically flared for transitioning from the smaller diameter ferrule body to the larger diameter shaft and for providing sufficient surface area for abutting the ferrule body and the shaft. The diameter at the base of the ferrule body is typically the same as or relatively larger than the diameter of the shaft. While some ferrules may have a variety of contours on their external surface, the effective diameter or cross-sectional area remains substantially the same as that of the shaft either throughout the length of the ferrule body and/or at the flared base.
As will be apparent to one skilled in the art, the diameter, and hence the surface area, of the ferrule affects the penetration of the broadhead. Accordingly, there exists a need for a ferrule having a diameter that is relatively smaller than the diameter of the shaft along the entire length of the ferrule.